The present invention relates to a method for producing a microcapsule with a sun protection effect and, more particularly, to a method using silica to produce microcapsules with micromized diameters to significantly increase the sun protection effect when applied to a skin of a user.
Ultraviolet (UV) rays can cause serious injury to the skin, including swelling, sunburn, pigmentation, aging, loosing elasticity, and wrinkles, and can even damage the skin immune system and increase the chance of getting skin cancer. The destruction to the environment aggravates the invasion of ultraviolet rays. Thus, sun protection should not be ignored.
Although UV filters can resist ultraviolet rays, the side effects, including irritation to the skin, inflammation of the skin, skin sensitization, and phototoxic reaction, are undesirable. Thus, it is desirable to research and develop effective sun protection products with minimal side effects to the skin while reducing the burden to the environment. Chemical UV filters achieve the sun protection effect through energy transfer. However, photodegradation occurs in some of the UV filters due to the energy provided by the ultraviolet rays, producing harmful free radicals and phototoxic substances while reducing the sun protection effect.
A silica microcapsule formed by a sol-gel/emulsion technique can provide a sun protection effect as physical UV filters. When used together with a chemical UV filter, the silica microcapsule can reduce the quantity demand of the chemical UV filter. The chemical UV filter can be entrapped by the silica microcapsule to avoid photodegradation and phototoxicity while avoiding direct contact with the skin to avoid allergic reaction.